Cash over installments question .

There is a question in my book which is:

Mr.Brown can pay for an article in either of the two ways. He can pay the list price with a down payment of 20% and the balance in 5 installments of $16 each or he can pay the cash price of $88.How much does he save by paying the cash price ?

The book says the answer is $12.00 but according to me its $9.60. Here is how i did it

20% of 88 is $17.6
The installments will cost him :16x5=80
So He has to pay a total of 17.6+80=97.6
The difference would then be 97.6-88=9.6Ans
Is my answer correct and that's a typo in the book or am i doing something wrong here ??